Least Sandpiper (Calidris minutilla)

[order] CHARADRIIFORMES | [family] Scolopacidae | [latin] Calidris minutilla | [UK] Least Sandpiper | [FR] Becasseau minuscule | [DE] Wiesen-Strandlaufer | [ES] Correlimos Menudillo | [NL] Kleinste Strandloper

Subspecies

Physical charateristics

The delicate Least Sandpiper is the world’s smallest shorebird. In breeding plumage, it is mostly brown, including the breast. It does not have the streaks and spots on its side that the Western Sandpiper has. The adult in non-breeding plumage is drab grey, with a dark breast. The bill is relatively short and fine-tipped, with a slight droop at the end. Its yellow legs distinguish it from the other peeps, Western and Semipalmated Sandpipers, which have black legs. In flight, the Least Sandpiper shows a white stripe down its wing and white on either sides of its tail. The underwings are slightly darker than those of the other two peeps, as well. Juveniles are also brownish, but may be brighter rufous than adults, especially in comparison to the faded fall breeding plumage of the adults.

Listen to the sound of Least Sandpiper

[audio:http://www.aviflevoland.nl/sounddb/L/Least Sandpiper.mp3]

Copyright remark: Most sounds derived from xeno-canto

Range

North America : North

Habitat

Least Sandpipers breed from the northern boreal forest to the sub-Arctic tundra. They typically nest in sedge meadows, muskeg bogs, or coastal wetlands. They migrate all across North America, and some migratory and wintering habitat is coastal, while some is inland. Coastal migrants can often be found along tidal creeks, salt marsh edges, and mudflats, rarely on sandy ocean beaches. Inland migrants inhabit small, shallow ponds, sandy riverbanks, sewage treatment ponds, and lakeshores.

Reproduction

Males arrive on the breeding grounds about a week before females and establish territories. Monogamous pairs form quickly after the females arrive. The nest is on the ground near water, and usually on a tuft of grass or moss. The male begins the shallow scrape, and the female finishes it, lining it with grass, leaves, and moss. Both parents help incubate the 4 eggs for about 20 days. As incubation progresses, the male takes a larger and larger share. The young leave the nest within a day of hatching, and feed themselves. The parents will brood and tend the young, and the male generally stays with the brood until they fledge at about three weeks. In later clutches, the female may actually leave before the young hatch, but usually she helps tend the young for the first week or so.

Feeding habits

Least Sandpipers usually roost by themselves or in small groups. They generally feed at the upper edge of mudflats, often in the vegetation, i.e., higher than Western or Semipalmated Sandpipers. When foraging, they walk slowly with their heads down, picking at food on the surface rather than probing into the mud.
On the breeding grounds and in inland areas, Least Sandpipers primarily eat fly larvae and other insects. On the coast, they eat small crustaceans, snails, and other marine creatures.

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Migration

Migratory. Migrates in broad front over interior North America to S USA, Greater Antilles, Gulf of Mexico and NW South America; E population crosses Atlantic Ocean from NE North America to Lesser Antilles and NE South America, but returns N through S North America or up coast; part of W population migrates down Pacific coast to NW South America. Some fidelity to wintering and staging sites. Adults precede juveniles during S migration, departing respectively from late Jun and mid-Jul, and adult females precede males; arrives N wintering grounds late Jun to Jul, in Suriname mostly Aug but juveniles mid-Aug to Oct; in California most birds disperse S in Nov. Migrates N across USA and Canada in May, up E USA coast Mid-Apr to mid-May, 1-2 weeks earlier on W coast; males arrive on breeding grounds c. 7 days earlier than females. Migrates in flocks of 10?s to 100?s.

Distribution map